188 AMERICAN MIDLAND NATURALIST 
I do not believe that Rhus Toxicodendron as the common name, 
without further specifications including the two allies now des- 
cribed and a large number of their kin would be satisfactory to 
the majority of botanists of the present day. 
Artemisia caudata calvens var. nov. 
Planta humilis, plerumque 1.5-3 dm. alta. Caules et folia 
juvenilia indumento denso, cano operta, quod in caule mox 
evanescit, nisi sparse, praecipue circum pétiolos, ubi saepe per- 
manet; in foliis omnino vel partim stabile est. Folia brevia, 3—6 
cm. longa. 
Rather low, usual length 1.5-3 dm. Stems and leaves covered 
with a thick, gray indument when young. This disappears soon 
on the stem, except in spots, especially around the petioles, where 
it often is permanent; on the leaves it is wholly or partly per- 
sistent. Leaves short, 3-6 cm. long. 
Collected by the writer in gravel at Willow City, Bottineau 
County, on August 26, 1889. . 
Leeds, North Dakota. 
THE TRITOGONIA TUBERCULATA MUDDLE. 
By S. W. GEISER. 
During the past few years, considerable confusion has arisen 
in regard to the proper names to be applied to the species de- 
scribed by Barnes, 1823, as Unio tuberculatus. The result is that 
a number of different names have been applied. With the purpose 
of correcting the nomenclature of a former geographic catalogue 
of mine, I began some time ago the study of the synonymy of this 
species. As a result of my studies it seemed advisable to apply 
a new name Quadrula Parkeri' to this species. 
In order to clear up the present confusion of names I have 
decided to take all the names that, so far as I can learn, have been 
applied to this species up to Nov. 1, rgr1. I shall first cive a list 
of the synonyms, and then separately discuss their availability 
as names for the present species. 
’ The Academician I.: 15. [Oct. 30, 1911]. 
